October 10, 2013
Douglas W. Allen, an economist at Simon Fraser University, in
Vancouver, has just published a highly controversial study in the
journal Review of Economics of the Household.
It breaks with the conventional wisdom that there is no difference
between parenting by a mother and a father and parenting by a same-sex
couple.
MercatorNet interviewed Professor Allen about his findings.
MercatorNet: What has your research found about
educational outcomes for children of same-sex couples versus children of
opposite sex couples?
Doug Allen: There have been about 60 studies over the
past 15 years or so that have asked “do child outcomes differ when the
child is raised in a same-sex household." Almost all of this literature
has the following characteristics: the samples are tiny and biased, the
outcome measures are subjective and difficult to replicate, and the
finding is always one of "no difference."
Despite the limited scientific validity of these studies, they all end
with sweeping policy recommendations. It really is not a scientific
literature, but rather a political literature targeted at judges,
lawyers, and politicians.
Then came a paper by Michael Rosenfeld, published in Demography
2010. This paper had a large random sample and looked at normal
progression though schools in the US. It was, in my opinion, the first
solid piece of statistical work done on the question, and he confirmed
the "no difference" finding. Later, Joe Price, Catherine Pakaluk, and
myself replicated his study and found two problems.
First, he didn't find "no difference". What he found was a lot of
noise, and so he was unable to statistically distinguish children in
same-sex households from children in any other type of household - including ones we know are not good for children.
Second, the lack of precision in his estimates came from a decision he
made to throw out children from the sample who had not lived in the
same location for five years. This turned out to be heavily correlated
with same-sex households. Hence, he inadvertently threw away most of the
same-sex households from the sample. Without that information, he did
not have the statistical power to distinguish between family types.
So, the three of us restored the sample and used the statistical
technique of controlling for household stability. What we found was that
children of same-sex households were about 35 percent more likely to
fail a grade.
While this was going on, I was using the Canada census to look at some
other questions. I noticed several things about the census that
differed from the US. one. First, unlike in the US, the Canada census
actually identifies same-sex couples. This solves a big measurement
problem with the US census, which could include room mates, family
members, and opposite sex couples as same-sex ones.
Second, the Canada census had a nice link between the children and the
parents, so I was able to control for the education of the parents and
their marital status. Poor performance in school is correlated with
marital disruptions of parents, so this is an important control. In many
ways then, the Canada census is a much better data set for addressing
this question, and I decided to simply redo the Rosenfeld study using
this data. (The census does not record progress through school, so I
examined high school graduation rates instead).
So, what did I find? First, I simply looked at how any child in a gay
or lesbian home did compared to children from married, cohabiting, and
single parent homes. Most of the discussion in the paper compares
children in same-sex homes to those in opposite sex married homes, but a
reader can do all of the comparisons by looking at the tables.
I found that on average, children in same-sex homes were about 65
percent as likely to graduate from high school, compared to similar
children in married opposite sex homes. That finding seems very similar
to the one we found in the US regarding normal progress. Next, I
wondered if the gender composition mattered at all, so I separated out
the boys and girls. I was very surprised by the results.
On the boy side, I just found a lot of noise. Some boys do well in
same-sex households; some do quite poorly. I cannot statistically
determine the effect.
Just looking at the point estimates, boys in lesbian homes are about
76 percent as likely to graduate, in gay homes they are about 60 percent
more likely to graduate. But neither of these are statistically significant, meaning they cannot be distinguished from zero.
Girls are another story. First, the estimates are very precise.
Second, they are low. A girl in a gay household is only 15 percent as
likely to graduate, in a lesbian household about 45 percent as likely.
The result found by lumping all of the children together is being driven
by this girl effect. This result is very robust, I tried many
specifications, sample restrictions, and estimation techniques, but it
always remained.
So, my paper no only rejects the "no difference" consensus, it points
to a finding -- that if upheld by other studies -- seems incredibly
important.
It's particularly hard on girls, isn't it? Why is that?
Allen: It is important to point out that I make no
theoretical claims in the paper. I'm simply pointing out an empirical
finding that is based on a high quality large random sample, and which
is inconsistent with almost everything that has come before.
Having said that, as an economist, I would make the following
speculation: specialization. It makes sense to me that fathers and
mothers are not perfect substitutes. Indeed, mothers may provide some
parenting services that a father cannot provide, and fathers may provide
parenting services that mothers cannot. These services may be necessary
for girls but not necessary for boys.
For example, I've been told by medical people that when a biological
father is present in the home, daughters begin menstruation at an older
age. Later menstruation is likely correlated with delayed sexual
activity, etc., and this may lead to a better likelihood of high school
completion.
It seems to me there could be dozens of channels this could work. As a
father of two girls and one boy, I've often had discussions with other
parents noting that with boys you just have to keep them fed and away
from explosives, but with girls rearing is a little more complicated.
That's a poor attempt at humour, but the bottom line is this is an
interesting question that deserves to be looked at.
One explanation of poor school performance in general is that children
of same-sex couples may be discriminated against at school. This seems
less likely given the different finding between boys or girls. Or at
least one would have to come up with a different more complicated story
of discrimination.
This turns the conventional wisdom on its head, doesn't it? Most
people think that there is no difference. Was there anything wrong with
the quality of previous research?
Allen: I think I've answered this above. I should
point out one other thing, however. I've read just about every paper on
this subject that has been published since 1995. Although many of them
claim to find "no difference", they often do find something. Again, the
finding is coming from a biased small sample, but differences are found.
For example, children growing up in same-sex homes are more likely to
experiment with alternative sexual lifestyles, etc.
I should also point out that not all studies are created equal. For
example, an Australian sociologist named Sotirios Sarantakos has done
considerable work in the 1990s that (though not random) uses large
longitudinal studies of objective, verifiable, and hard measures of
performance. He finds many differences with children in same-sex
households in terms of mathematics, language and other school
performance measures. Interestingly, his work is never referenced in
most literature surveys. Again, this points to the political nature of
this literature.
Your conclusions are based on Canadian census data. Why is that better than US data?
Allen: I've mentioned this above, but let me give
more detail. The US census does not identify same-sex cohabiting or
married couples. So how did Rosenfeld and others find them? They looked
at a series of questions: for example, what is your sex, are you
married, what is the sex of your spouse? If someone answered male / yes / male, then this would be considered a gay couple.
The problem with this is that it can lead to a number of measurement
issues. Suppose I'm a married man, bunking with another man in a work
camp (this may seem far fetched, but it is a real example). When I
answer the survey I say I'm male, I'm married, and I'm currently living
with a male. I may get counted as a same-sex couple even though I'm not.
This can happen with same-sex family members who live together, room
mates, and others.
There is also the problem of random mistakes. No one fills out a form
perfectly, and sometimes the wrong box is ticked off. Because there are
so many heterosexuals compared to gays and lesbians, it only takes a
small fraction of seniors to tick off the wrong sex box and it can swamp
the same-sex sample. The Canada census avoids these problems. It not
only identifies same-sex couples, but they must be in a cohabiting or
marriage relationship.
Canada has also had legal same-sex marriage before the census was
taken. Many have argued that Canada is more open and accepting of
same-sex marriage. As a result, the reporting bias is likely lower in
Canada than in the US.
Finally, as mentioned above, I was able to control for the marital
history of the parents. This also turns out to be statistically
important, and in the paper I show what happens when this is not
controlled for. Children in same-sex households are much more likely to
come from a previous heterosexual marriage than from adoption or other
means. Divorce, however, reduces the likelihood of graduation. If you
don't control for this effect, children of same-sex households look like
they do even worse at graduation. So this is an important variable to
consider.
Does your study prove conclusively that there is no difference? What questions does it raise?
Allen: Assuming there are no mistakes in the study,
it rejects the claim that there is "no difference." I personally think
that in social science we should never place too much weight on a given
study. It is important that we look at evidence from different
countries, etc. I would say this study builds on a few others that are
questioning the long held consensus. An examination of the literature
shows that the consensus is built on only a series of preliminary work.
Now that people have started looking at this more seriously, we're
finding no evidence for that conclusion.
In such a contentious field, will your study make an impact upon the public debate?
Allen: I don't know, but I suspect it will have
little impact. The debate seems to have shifted from the statistical lab
to the bumper sticker. The concept of "marriage equality" and the
alignment of same-sex marriage rights with the civil rights movement
seems so powerful that I doubt one little study will matter much.
If there is merit to the study, and if there really is a difference
that matters, I think it is much more likely that 20 years from now
we'll be asking "how did we get here and how can we clean up the mess"
-- in much the way we now wonder how we ended up in a world where so
many children are raised by single parents.
Sociologist Mark Regnerus published a paper which came to a
similar conclusion last year and was all but crucified by his colleagues
and activists. Do you expect a similar reaction?
Allen: Prior to the publication of his paper I was
unaware of Professor Regnerus' existence. Because I was working in this
area I saw what immediately happened. I was struck by the hypocrisy of
those who attacked him.
Here was someone who had looked at the literature and decided to do
something better. There were tiny samples, so he went and found a large
sample. There was nothing but bias and snowballing (the procedure of
asking friends to join a study), so he did a random procedure. There was
way too much soft-balling of questions, so he asked a series of
quantifiable ones. He was trying to improve the work, and that is
commendable.
Was his study perfect? No, but a study never is. His great error, of
course, was that he found the wrong answer. Those who came later and
complained about the things he did should have been equally outraged by
what had come before. Had Regnerus found otherwise, they would have
lauded his work as path-breaking.
I rather suspect this will not happen to me for a number of reasons. First, after the Demography
comment came out last year, my university received several letters
(sent to the president, various other administrators, and many of my
colleagues) demanding that I be fired. These were the same tactics that
were used against Professor Regnerus.
Fortunately for me, I'm well known and respected at my institution and
we have a strong sense of academic freedom. Indeed, Simon Fraser
University has recently been ranked as one of the safest universities to
express ideas that may be politically incorrect.
Second, my study only looks at one margin of child performance: high
school graduation. Professor Regnerus looked at many and in many ways he
found more problems than I found.
Third, my sample is a 20 percent sample of the Canada census. No one
can claim I have a small biased sample or that the agency in charge of
collecting it is not trustworthy. Fourth, Professor Regnerus was first,
and I think being first is much more likely to come under fire. Fifth,
the US Supreme Court has already made a decision on Prop 8 and DOMA, so
much of the incentive to attack has passed.
Having said that, I have come under some attack, and I would like to relay one incident that has happened.
Last week I received an email from David Badash,
the editor of The New Civil Rights Movement, a prominent gay rights
website. In it he said he'd heard about the study, wasn't happy about
it, but wanted to talk to me before he wrote about it. I emailed back,
sent him a copy, and invited him to ask me any questions about the work.
On Monday, when I arrived at work, there were a number of colourful
emails waiting for me, calling me all kinds of four-letter words. I soon
realized that these were coming from people who had read Mr Badash's blog page.
So I went to have a look myself. What I found was a mixture of
personal attacks, misunderstandings and misrepresentations of my work,
and a general meanspiritedness. Just the opposite of what I've always
believed a public discussion should be.
So, maybe I'm naive, maybe the attacks will come. I hope not. Anyone
who wants to read my work is welcome, and I'm willing to have a
reasonable discussion about it with anyone.
Douglas W. Allen is the Burnaby Mountain Professor of economics at
Simon Fraser University in Burnaby, British Columbia, where he earned
his undergraduate degree. He has a PhD in economics from the University
of Washington, and is the author of four books and numerous articles.